HK80UTM_TO_HK80GEO: Convert the HK80UTM coordinates to HK80GEO coordinates

In HK80: Conversion Tools for HK80 Geographical Coordinate System

Description

Convert the HK80UTM coordinates to HK80GEO coordinates

Usage

HK80UTM_TO_HK80GEO(N, E, zone = c(49, 50))

Arguments

N	Numeric, Northern coordinate in meters.
E	Numeric, Eastern coordinate in meters.
zone	zone, UTM zone, either 49 or 50 for Hong Kong.

Details

This function uses equation 3, 4, 5 in the explanatory notes to convert the HK80UTM coordinates into HK80GEO coordinates (latitude and longitude) in decimal degrees. Mode details could be found at: Page C9 and C10 on the explanatory notes.

Value

latitude	latitude in decimal degrees
longitude	longitude in decimal degrees

Note

The coordinates should be within the range of Hong Kong. Providing coordinates outside Hong Kong will lead to wrong results.

Author(s)

Jinlong Zhang

References

Survey & Mapping Office Lands Department, Hong Kong Government (1995). Explanatory Notes on Geodetic Datums in Hong Kong, available at: http://www.geodetic.gov.hk/smo/gsi/data/pdf/explanatorynotes.pdf

See Also

HK80GEO_TO_HK80UTM

Examples

options(digits = 15)
HK80UTM_TO_HK80GEO(2483775, 208930, zone = 50)

#### $latitude
#### [1] 22.435188997523
#### 
#### $longitude
#### [1] 114.172349350774

##### Answer from the explanatory note:
### 22 + 26/60 + 06.89/3600 = 22.43524722
### 114 + 10/60 + 20.39/3600 = 114.1723306

Example output

         latitude        longitude
1 22.435188997523 114.172349350774

HK80 documentation built on May 2, 2019, 2:10 a.m.